math354-01.go

package main

import "fmt"

func main() {
	max := 1000
	for a := 0; a < 8; a++ {
		for b := 0; b < 8; b++ {

			func(a, b int) {
				initA := a
				initB := b
				i := 0

				defer func() {
					if i < max && i > 0 {
						fmt.Printf("(a:%4d, b:%4d)\t%-4d\t(a:%4d, b:%4d)\n", initA, initB, i, a, b)
					}
				}()

				history := [][2]int{}
				for a > 0 {

					if a < b {
						a, b = 2*a, b-a
					} else {
						a, b = a-b, 2*b
					}
					i++
					if i > max {
						return
					}

					fmt.Printf("\t[step: %2d] (a:%4d, b:%4d)\n", i, a, b)
					for _, tuple := range history {
						if tuple[0] == a && tuple[1] == b {
							fmt.Println("ERROR WILL LOOP")
							return
						}
					}
					history = append(history, [2]int{a, b})
				}
			}(a, b)

		}
	}
}